I'm trying to replicate the weigh scale project and I'm running into some difficulties. I believe the Python program is running correctly and the microcontroller was programmed properly.

However, when I unplug the USB serial cable, switch from "program" to "run" mode, and plug it back in, my wireless mouse stops working and my cursor keeps darting to the lower left hand corner of the screen. The pygame program doesn't do anything, staying at 0.0 Current and 0.0 Peak. I then unplug the USB serial cable and my mouse still doesn't work properly until I log out of Windows and log back in.

When the board is powered up, my multimeter reads 2.2V at PD3, 2.6V at PD4, and 4V at PC0 (which doesn't seem to change when I apply pressure to the Wheatstone bridge).